DSpace@ATÜ (Adana Alparslan Türkeş Bilim ve Teknoloji Universiti)
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Bio-MOF'lar kullanılarak ekshale gaz karışımlarından anestezik Xe geri kazanımının moleküler modellenmesi
No full textLisansüstü Eğitim Enstitüsü, Biyomühendislik Ana Bilim DalıXenon (Xe) için ucuz ve verimli bir geri kazanım süreci tasarlamak, sürdürülebilir uygulamaların geliştirilmesinde önem kazanmaktadır. Xe'yi anestezik gaz karışımlarından ayırmak için metal organik çerçevelerin (MOF'lar) kullanılması, literatürde nadiren ve yüzeysel olarak incelenen bir konudur. Bu tezde, biyo-uyumlu metal katyonlar ve biyolojik bağlayıcılar tarafından oluşturulan 43 biyolojik MOF'un (Bio-MOF) Xe geri kazanım performansları teorik olarak araştırılmıştır. CO2, O2 ve N2 ile ikili karışımlarındaki Xe alımları ve Xe geçirgenlikleri, Grand Canonical Monte Carlo ve Molecular Dynamics simülasyonları uygulanarak hesaplanmıştır. Metaloporfirin, hekzakarboksilat, triazin veya pirazol ligandları, dimetalik birimleri, nispeten büyük gözenek boyutları (PLD>5 Å ve LCD>10 Å), boşluk fraksiyonları (?0,8) ve geniş yüzey alanları (>2900 m2/g) içeren malzemeler Xe geri kazanımı için en yüksek performanslı Bio-MOF'lar olarak belirlenmiştir. Sonuçlarımız, Xe'nin nanogözenekli malzemelerdeki seçici adsorpsiyonunda kritik bir rol oynayan, nadiren incelenen aerojen etkileşimlerinin örneklerini göstermektedir.Designing an in expensive and highly efficient recovery process for Xenon (Xe) is gaining importance in the development of sustainable applications. Using metal organic frameworks (MOFs) for separating Xe from anesthetic gas mixtures has been a recent topic studied rarely and superficially in the literature. In this thesis, we theoretically investigate Xe recovery performances of 43 biological MOFs (Bio-MOFs) formed by biocompatible metal cations and biological endogenous linkers. Xe uptakes and Xe permeabilities in its binary mixtures with CO2, O2, and N2 are investigated by applying Grand Canonical Monte Carlo and Molecular Dynamics simulations. Materials having metalloporphyrin, hexacarboxylate, triazine, or pyrazole ligands, dimetallic paddlewheel units, relatively large pore sizes (PLD>5 Å and LCD>10 Å), large void fractions (?0.8), and large surface areas (>2900 m2/g) are determined as top performing Bio-MOFs for Xe recovery. The results of this thesis show examples of rarely studied aerogen interactions that play a critical role in selective adsorption of Xe in nanoporous materials
Development of Neural Network-Based Asphalt Mix Design Parameters Prediction Tool
No full textMix design of asphalt concrete is carried out in order to produce a mixture of asphalt bitumen and aggregate that satisfies both minimum design requirements and cost-effectiveness. Marshall mix design, similar to other mix design methods, aims to determine an optimum mix for a given design criteria, having an optimum bitumen content, and has still been one of the most used asphalt mix design method in the world. Marshall mix design procedure requires significant amount of time and skilled workmanship for lengthy laboratory experiments. Time required for the mix design may negatively affect construction schedule especially during the peak construction season. In Marshall mix design procedure, optimum bitumen content is determined based on Marshall stability and flow test results, and other volumetric properties of the mixes. Prediction models that quickly predict all required Marshall mix design parameters based on very few numbers of input parameters requiring significantly less amount of time to obtain compared to the time needed to obtain all Marshall mix design parameters through lengthy laboratory experiments could be quite useful. In this study, artificial neural network-based prediction models based on the data of 200 asphalt mixes designed for asphalt wearing course, obtained from 5th district of the General Directorate of Highways of Turkey, were developed to predict all required Marshall mix design parameters. As part of the paper, a Microsoft Excel Macro-based tool, to be potentially used by 5th district of the General Directorate of Highways of Turkey, was also developed that makes prediction of all required mix design parameters for any given mix in seconds using the developed models and very few numbers of user-defined input parameters requiring significantly less amount time to obtain so that optimum bitumen content could be quickly determined. This will significantly reduce the amount of time and other resources required to determine optimum bitumen content
Os fatores que afetam o uso de aplicativos móveis de turismo
No full textThe purpose of this study is to determine the key factors affecting the behaviour of using tourism mobile apps. Contrary to previous studies, the present paper highlights the key factors by evaluating the perceived advantages and technological self-efficacy together. So as to evaluate overall measurement quality and test the hypothesised relationships, a two-step approach was applied. In the first step, confirmatory factor analysis (CFA) was employed to test the validity of the measurement scales. Then, the dataset was analysed using the PLS-SEM method to test the proposed hypotheses. Data were collected from 213 adult participants through an online survey. The study revealed that time-saving is a key determinant of tourism mobile apps usage with the highest beta coefficient (0.335, p<0.01). The effects of convenience (0.293) and technological self-efficacy (0.201) were also significant and positive. However, the perceived financial advantage does not have a significant effect on the behaviour of tourism mobile apps usage. Given the growing value and market potential of mobile applications, this research provides crucial empirical evidence for application developers and tourism researchers about the use of mobile applications for the tourism industry
An Ancient Debate: Are There Any Industrial Facilities on Chemical Weapons in Ottoman?
No full textThe primary occupation of the states in the modern period is to manage the perception of the warfare in progress. Therefore, the humane factor in scientific investigation was articulated to this insane process. The insufficiency of the major weapons was evident in the very beginning of the WWI. So, the evolving nature of the war strategy, the integration of the area behind the front lines and the unforeseen period of the war broke out a great despair among the armed forces. Thus, the states took new ways to update the elements of violence in their agenda. They had chemicals, gas and suffocative elements in their pocket and set forth a proper plan to use them. This study aims to reveal the general areas of usage of chemical weapons and to discuss the awesome effects of them in trench warfare and war of attrition along with its analysis in Ottoman Army
Cechy geologiczne, petrograficzne, mineralogiczne, geochemiczne i gemmologiczne rubinów z Malatyi
No full textThere are significant ruby formations across the world that have been commercialized. In Turkiye there are many mineralogical formation regions with gemological features of high quality. However, there is not enough information in the literature about the formation of ruby in Turkiye, and its usability as a precious stone. In contrast to previous studies, this paper was conducted to reveal the gemological properties of Dogansehir (Malatya province) rubies and to investigate the usability of polished and cut ruby samples as gemstones. Ruby corundum formations of gemstone quality have recently been discovered in Goksun ophiolites in the Dogansehir district of Turkiye. These ruby formations take place in greenish and grayish amphibolites in the Goksun ophiolites. The ruby crystals are observed in colors ranging from pink to red and sizes ranging between 2 x 10 mm and 30 x 50 mm. The tectonic position, geological environment, petrographic, mineralogical, geochemical, and gemological characteristics of Dogansehir crystals indicate that they can be classified as rubies and can be likened to those gems formed in amphibolites in Tanzania. This indicates that Dogansehir rubies have gemological and mineralogical parameters that are competitive with rubies existing in other places across the world after polishing and cutting. Examples of Dogansehir rubies prepared by polishing and cutting show that these rubies may feature in the global market in the coming years. Dogansehir rubies are suitable for COBACORE (community based comprehensive recovery) cutting mostly in large sizes and amounts. Thus, it is a potential gemstone source. Samples prepared by polishing and cutting indicate their suitability as gemstones
Novel Frequency-Reconfigurable Antennas with Ring Resonators and RF Switches: Enhancing Versatility and Adaptability in Wireless Communication Systems
No full textThis study introduces innovative designs for frequency-reconfigurable antennas that utilize ring resonators combined with either PIN diodes or RF switches. These designs enhance the versatility, adaptability, and overall performance of the antennas in wireless communication systems. By controlling the switches and ring resonator, the antenna's resonant frequencies and bandwidths can be adjusted, allowing for compatibility with various communication standards and frequency ranges. The proposed antenna exhibits four distinct operational states, each characterized by different resonance frequencies and operating frequency bands. Return loss, radiation pattern, radiation efficiency, and surface current distribution are analyzed for each state. State-1 (ON-ON) and State-2 (OFF-ON), which are characterized by resonance frequencies of 2.4 GHz and 3.33 GHz respectively, offer ranges suitable for Wi-Fi, Bluetooth, ISM, and IoT applications. State-3 (ON-OFF), with a resonance frequency of 3.0 GHz and bandwidth spanning from 2.59 GHz to 3.643 GHz, complies with Wi-Fi, Wi-Fi 6, and IoT requirements. State-4 (OFF-OFF) covers the band centered around 3.45 GHz. It is compatible with many applications such as 5G mid-band, Wi-Fi 6E, IoT, and cellular systems. The proposed antenna designs are versatile and compact since the overall antenna dimensions are 25 x 18 x 1.6 mm(3). The radiation efficiency of the antenna configuration varies depending on operational states. By utilizing the advantages of both ring resonators and RF switches, the proposed antenna configurations offer new solutions that enhance their performance in wireless communication systems. This study compares the effects of using PIN diodes and SPDT switches on the performance of antennas and also examines the DC biasing effect on antenna characteristics. The simulation results are validated by the experimental analysis. The proposed antenna designs offer a new approach for wireless communication systems by using both ring resonators and RF switches.Scientific Research Projects Unit (BAP) in Adana Alparslan Turkes Science and Technology University [21803003]This work is supported by the Scientific Research Projects Unit (BAP) in Adana Alparslan Turkes Science and Technology University. Project No: 21803003
Examination of the presence of ocratoxin a and aflatoxin in dried figs
No full textLisansüstü Eğitim Enstitüsü, Gıda Mühendisliği Ana Bilim DalıBu çalışmada Adana ilindeki toptan/perakende satış noktalarından alınan kuru incirlerin kalite parametreleri araştırılmıştır. Çalışma kapsamında 21 farklı kuru incir örneğinde mikotoksin (HPLC-FLD yöntemi), antioksidan kapasite (DPPH ve ABTS yöntemi), toplam fenolik madde, şeker ve genel bileşim analizleri yapılarak fiziksel, kimyasal ve biyoaktif özellikleri değerlendirilmiştir. Piyasadan toplanan kuru incir numunelerinin, aflatoksin değerlendirmelerinde ürünlerin %9.5'nin Türk Gıda Kodeksi Bulaşanlar Yönetmeliğinde yer alan doğrudan insan tüketimine sunulan veya gıda bileşeni olarak kullanılan kurutulmuş meyvelerde aflatoksin B1 ve toplam aflatoksin (B1+B2+G1+G2) limitlerini (8-10 µg/kg) aştığı ve ilgili yönetmeliğe uygun olmadığı belirlenmiştir. P kodlu numunenin aflatoksin B1 değeri 15.6 µg/kg, T numunesinin aflatoksin B1 değeri 836.9 µg/kg olarak tespit edilmiştir. Kuru incir numunelerinde, ayrıca okratoksin A analizleri yapılmış olup 5 Ağustos 2022 tarihli Komisyon Yönetmeliği (AB) 2022/1370 kuru incir meyvelerine belirlenmiş limit olan 8 µg/kg değeri kriter olarak kabul edilerek sonuçların %14'ünün bu belirtilen limiti aştığı tespit edilmiştir. Kuru incirlerin antioksidan kapasitesi ABTS ve DPPH olmak üzere iki farklı yöntemle belirlenmiştir. ABTS yönteminde antioksidan kapasite potansiyeli en yüksek T örneğinde 13670 µmol trolox /kg ve en düşük C örneğinde 6757 µmol trolox /kg olarak tespit edilmiştir. DPPH yönteminde antioksidan kapasite yine aynı şekilde en yüksek T örneğinde 5467 µmol trolox /kg ve en düşük 2962 µmol trolox /kg olarak tespit edilmiştir. Fenolik bileşik ile antioksidan kapasite (DPPH ve ABTS yöntemleri) arasında yüksek korelasyon değerleri saptanmıştır. Kuru incirlerde yapılan şeker analizlerinde sakkaroz, glikoz ve fruktoz bileşikleri belirlenmiştir. Glikoz (G) ve fruktoz (F) baskın şekerler olarak saptanmış ve G/F oranı yaklaşık 1,5 olarak belirlenmiştir. 21 adet kuru incir örneğinin glikoz miktarı ve sakkaroz miktarı en düşük N örneğinde saptanmıştır. Kuru incirlerin toplam fenolik madde içerikleri en yüksek T örneğinde 2696 mg GAE/ kg ve en düşük C örneğinde 1316 mg GAE/ kg olduğu tespit edilmiş olup, T örneğinin diğer örneklerden daha zengin olduğu saptanmıştır.In this study; The quality parameters of dried figs purchased from wholesale/retail outlets in Adana were investigated. Scope of work; Mycotoxin (HPLC-FLD method), antioxidant capacity (DPPH and ABTS method), total phenolic substance (UV spectrophotometer method) and sugar analysis (LC-2030C-RID method) analyzes of dried figs taken from 21 different places and their physical, chemical and bioactive properties examined. Aflatoxin analyzes were made of dried fig samples collected from the market, and 9.5% of the results obtained were aflatoxin B1 and total aflatoxin (B1 +B2+G1+G2) in dried fruits that are offered for direct human consumption or used as food ingredient, which are included in the Turkish Food Codex Contaminants Regulation. It was determined that the limits exceeded the 8-10 µg/kg limit and were not in compliance with the relevant regulation. The aflatoxin B1 value of the P sample was 15.6 µg/kg, and the aflatoxin B1 value of the T sample was 836.9 µg/kg. Dried fig samples; The amount of ochratoxin A was analyzed and it was determined that 14% of the results exceeded this limit by accepting the 8 µg/kg value, which is the limit determined for dried fig fruits in the Commission Regulation (EU) 2022/1370 dated 5 August 2022. The antioxidant capacity of dried figs was determined by two different methods, ABTS and DPPH. In the ABTS method, the antioxidant capacity potential was determined as 13670 µmol trolox /kg in the T sample with the highest and 6757 µmol trolox /kg in the lowest sample C. In the DPPH method, the antioxidant capacity was determined as 5467 µmol trolox /kg and the lowest as 2962 µmol trolox /kg in the T sample. A high correlation between the scientifically expected DPPH and ABTS methods was also observed in the analyzes of the samples used. Sucrose, glucose and fructose compounds were determined in sugar analyzes made in dried figs. In the data obtained in the study, it was observed that glucose was the primary sugar in all samples. Glucose and fructose sugars are dominant and the G/F ratio is around 1.5. Glucose content and sucrose content of 21 dried fig samples were determined in the lowest N sample. The total phenolic content of dried figs was found to be 2696 mg GAE/kg in the highest T sample and 1316 mg GAE/kg in the lowest C sample, and the T sample was found to be richer than the other samples
Spatial infection control in burn center organization: a burn center design experience for evidence-based architecture
No full textPurposeThis study discusses that the necessary criteria and the solution approach taken to resolve the main spatial infection problems with a burn center design should be evaluated holistically to achieve spatial infection control in a burn center. The burn center design plays an important role in protecting severely burned patients from infection because the microbial flora of the hospital can affect the infection risk. In hospitals, sterilization and disinfection are the basic components of infection prevention; however, the prevention and control of infection for burn patients also requires the design of burn centers that adhere to a specific set of criteria that considers spatial infection control in addition to appropriate burn treatment methods and treatments. In this study, a burn facility converted from a burn unit into a burn center is introduced and the necessary design inputs for the transformation are discussed because there is no holistic study in the literature that delas with all the spaces that should be in a burn center and relations between spaces. This study aims to define the functional relations between each of the units and the spaces that change according to different sterilization demands in the burn center for ensuring spatial infection control. Furthermore, it aims to propose a method for ensuring continuity in the control of spatial infections. Design/methodology/approachThe burn care and health facilities guidelines are examined within the framework of spatial standards, together with a comprehensive literature review. The design method was based on the spread of microorganisms and the effect of human movement on space and spatial transitions in the burn center, according to all relevant literature reviews. To determine the extent to which the differences in treatment protocols of burn care guidelines were reflected in the space, interviews were conducted with burn facility officials. The plan-do-check-act (PDCA) method is also modeled to ensure the continuity of infection control in the burn center. FindingsThe burn center design findings are classified under three main headings, namely, location of the burn center in the hospital, spatial organization and physical features of the burn center and the air flowing system. The importance of the interactions among the criteria for spatial infection control has been revealed. Due to the physical space characteristics and air flow characteristics that change according to human movement and the way microorganisms spread, it has been seen that designing the air flow and architectural aspects together has an effective role in providing spatial infection control. Accordingly, a functional relation scheme for the center has been suggested. It is also proposed as a model to ensure the continuity of infection control in the burn center. Practical implicationsThis research presents spatial measures for infection control in burn centers for practitioners in health-care settings such as designers, engineers, doctors and nurses. The PDCA method also leads to continuity of infection control for hospital management. Originality/valueThis is the first study, to the best of the authors' knowledge, to focus on developing the criteria for spatial infection control in burn center. Moreover, the aim is to create a function chart that encompasses the relationships between the units within the burn center design so that infection control can be coordinated spatially
A Case Study on National Electricity Blackout of Turkey
No full textThe necessary precautions should be taken in order to prevent service interruption during the maintenance and repairing of electricity networks. Among these measures, emergencies that may occur in the network should be foreseen, hazard scenarios should be created, and solutions should be developed. If these are not done, a blackout, which first follows the local regions and eventually results in the collapse of the national electrical network, may take place. In this study, the national blackout of Turkey that occurred on 31 March 2015 is examined. The information about Turkey's electrical infrastructure and its energy policies was provided, as well as the reliability assessment criteria for power systems and examples of significant blackouts that occurred worldwide. The direct relation between line voltage and system frequency was provided with mathematical derivation by using real data taken from a local industrial zone. Then, a case study is presented to demonstrate this direct relation. The causes, development process, and consequences of the blackout are discussed in detail, and some recommendations are offered to increase the security of the electrical infrastructure and to prevent future occurrences while ensuring the sustainability of the system
A financial performance evaluation of commercial banks traded on Borsa Istanbul with a multi-dimensional perspective
No full textGiven that Turkey is an emerging market, it cannot be denied that the banks whose shares are traded on the stock exchange primarily lead the stock market and at the same time the Turkish financial markets. Therefore, a total of eleven commercial banks traded on Borsa Istanbul (BIST) have been included in the study. Since the performance of these commercial banks is evaluated in terms of multiple selected financial ratios (criteria), this study points out that it may be considered as a multi-criteria decision-making (MCDM) problem. Therefore, two effective MCDM techniques have been used in the performance evaluation process of the study. The aim of this study is to evaluate the performance of eleven commercial banks traded on BIST with a set of reasonable assessment criteria by using the integration of the criteria importance through intercriteria correlation (CRITIC) and weighted aggregated sum product assessment (WASPAS) methods for the year 2018. Copyright © 2023 Inderscience Enterprises Ltd